I tried to introduce new modules where it made sense. I deleted the
weird goroot test because I removed the optimization it was testing in
an earlier CL.
Change-Id: I219ddaa4f462a4aeb640f62215d16f246511a5fe
Reviewed-on: https://go-review.googlesource.com/c/144497
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>